1. Field of the Invention
The present invention relates to updating of filter tap coefficients of an equalizer, and more particularly, to an apparatus and method for updating filter tap coefficients of an equalizer, where the filter tap coefficients of the equalizer are normally updated without errors even when a defect is generated on an optical disc or track jumping occurs in an optical disc recording/reproducing apparatus.
2. Description of the Related Art
In order to increase a recording density of an optical disc, a partial response maximum likelihood (PRML) reading technique adopting a Viterbi decoding technique is used. An equalizer having a finite impulse response (FIR) filter unit including a plurality of digital filters is installed at a front portion of a Viterbi decoder, and equalizes waveforms of a radio frequency (RF) signal reflected by an optical disc so that the RF signal has a level required by the Viterbi decoder.
However, if defects exist on the optical disc or track jumping occurs, the RF signal becomes unstable. Accordingly, an error is generated in updating filter tap coefficients of the equalizer, so that the filter tap coefficients are diffused to unstable area values. Therefore, the equalizer becomes unstable, and, thus, freezing or breaking of image screens occurs.